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Updated: May 23, 2026

Assessment of Vascular Tone Responsiveness using Isolated Mesenteric Arteries with a Focus on Modulation by Perivascular Adipose Tissues
Published on: June 3, 2019
[Preoperative α-receptor block in patients with pheochromocytoma? Against]
1Klinik für Anästhesiologie, Intensiv- und Schmerztherapie, Kliniken Essen-Mitte, Henricistr. 92, 45136, Essen, Deutschland. h.groeben@kliniken-essen-mitte.de
Abstract:
Perioperative mortality regarding the resection of catecholamine-producing tumors has been markedly improved. This improvement has been attributed to the preoperative treatment with α-receptor blocking agents. An α-receptor block is still recommended prior to the resection of pheochromocytoma or paraganglioma. However, the effect has never been tested in a randomized clinical trial. Despite an assumed effective α-receptor block, many centers report systolic blood pressure increases beyond 200 mmHg. Out of 200 consecutive resections of catecholamine-producing tumors, 73 patients without an α-receptor blockade were treated. There was no significant difference in the maximum systolic blood pressure or in the incidence of hypertensive episodes. There was no correlation between the individual dose of phenoxybenzamine and the maximum blood pressure. Overall it can be concluded that with the improvement of surgical techniques, diagnostic tools and highly effective short acting substances to control hemodynamics intraoperatively, the question must be raised whether a time-consuming, unreliable pretreatment burdened with significant side effects is still required.
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